Synthesising Copper Oxide Nanoparticles and Investigating the Effect of Dispersion Medium Parameters on their Aggregate Stability

Abstract

We developed a technique for synthesising gelatin-stabilised copper oxide nanoparticles. The method behind the synthesis was direct deposition, while the copper oxide precursors used were copper sulphate, chloride and acetate. We employed gelatin as a stabiliser. We employed X-ray diffraction analysis to study the effect that the copper-containing precursor may have on the phase composition in the samples. We found that using copper(II) chloride yields two different modifications of copper(II) hydroxychloride (atacamite and clinoatacamite), while copper(II) sulphate yields brochantite. We established that copper oxide forms only when using copper(II) acetate. Dynamic light scattering data shows that a monomodal size distribution with an average hydrodynamic radius of 61 nm characterises the copper oxide nanoparticles. Investigating the effect that active acidity of the medium may have on the aggregate stability of gelatin-stabilized copper oxide nanoparticles showed that the sample is stable in the pH range of 6.8--11.98. The paper presents the mechanism behind the effect of active acidity of a medium on stability of copper oxide nanoparticles. We investigated how the ionic strength of the solution affects the stability of copper oxide nanoparticle sol. We determined that Ca2+ ions have the greatest effect on the sample